On Friday, April 3, a man barricaded the back door of an immigrant center in Binghamton, NY, USA with his car, then went in through the front door and began shooting people.
He killed thirteen people before killing himself.

On Saturday, April 4, a father in Graham, Washington, USA shot his five children (ages 7 – 16) to death and then killed himself.

Also on Saturday, April 4, police in Pittsburgh, Pennsylvania, USA responded to a call about domestic violence. When they arrived at the house, a 23-year-old man wearing a bullet-proof vest shot the three responding officers.SWAT officers arrived soon after but were unable to help the shot officers for hours because the man in the house held them at bay with gunfire.
By the time the three officers who were shot were retrieved by the SWAT team, they had bled to death.

And possibly due to global warming:

A large ice bridge in the Antarctic Ocean has collapsed.
Scientists say it was holding a huge ice shelf in place and now that it’s fallen, the ice shelf (which is the size of Jamaica) will begin to float away which may cause it to melt and raise the sea level.

Not totally unexpected, but North Korea launched the missile* that it had been getting ready.
(*North Korea claims that it isn’t a missile…but a satellite.)
It flew over Japan. Part of it landed in 日本海 (the Sea Of Japan) and the main part of the missile flew over Japan and landed in 太平洋 (the Pacific Ocean).
If any part of the missile entered Japan’s land, air, or sea borders, Japan was prepared to shoot it down.
Here is a YouTube video of CNN‘s coverage of the launch and Japan’s reaction: